Science fiction has introduced us all to the idea of traveling into the past – but is it really possible?

Sean Carroll talks bout how time travel would possibly work in the context of Einstein’s theory of general relativity, including the hypothetical idea of wormholes connecting distant regions of space. Dr. Carroll also explores the logical structure of time travel, and what it implies about predestination and free will. In the end, time travel is probably not possible, but by taking the idea seriously we help understand how the universe works.

Dr. Carroll is a Senior Research Associate in Physics at the California Institute of Technology. His most recent book is “From Eternity to Here: The Quest for the Ultimate Theory of Time”, a popular book on cosmology and the arrow of time. He is a contributor to the blog Cosmic Variance.